In distributed building systems it is known for power supplies of building system devices to be connected to a source of electrical power through a circuit breaker. Such power supplies have a characteristic of creating an in-rush current surge at start-up. When multiple power supplies are energized via a single circuit breaker contact, the overall current surge due to in-rush can create a current flow that is ten times the steady state current requirement.
In particular, many power supplies include an output capacitor that provides a DC output supply voltage during normal operation. During start-up, the capacitor acts as a short circuit temporarily, drawing excess current. This temporary current is referred to as in-rush current.
A consequence of such power supply in-rush current is that the circuit breakers can become overloaded and erroneously interrupt the circuit. There is a need for an arrangement that can reduce the likelihood of erroneous interruption of circuit that provides power to multiple power supplies of building system devices.